In convection-enhanced delivery (CED), drugs are infused locally into tissue through a needle, cannula, or microcatheter inserted into the tissue. Transport of the infused material is dominated by convection, which enhances drug penetration into the target tissue compared with diffusion-mediated delivery or systemic delivery.
The devices used to perform CED, as well as devices used in several other fields, can include a very small, thin tip (e.g., a microfabricated tip). For example, as shown in FIG. 1, a microcatheter 100 can include a catheter body 102 with a microfabricated tip 104 at the distal end thereof. The tip can be damaged or broken during handling and/or during a surgical procedure. For example, the tip can either break during handling as a user hits the catheter tip against an object, or the surgeon may break the tip while inserting it in the brain through a stereotactic system. Stereotactic systems generally have a lumen with a small inside diameter (ID) to snugly fit the catheter. For example, as shown in FIG. 2, an exemplary stereotactic system 200 has a small-diameter central lumen 202 extending therethrough. The surgeon is required to “aim” the small catheter into the tight lumen to get the catheter loaded into the stereotactic system. Catheters with small tips may get damaged as the surgeon may hit the tip against the stereotactic system while manually trying to align the catheter to the small lumen. In addition, stereotactic systems are generally sized for larger instruments and cannot adequately support and protect catheters with small diameters or small tips.
A need exists for methods and devices for protecting catheter tips and stereotactic fixtures for microcatheters.